While you may not be able to manage the full battery of strength work you were doing, you can incorporate basic work into your warm-up or cooldown through such routines as the myrtl, lunge matrix or Cannonball sequences. Basic core or leg exercises like calf raises, planks, squats, deadlifts and push-ups can be quickly added after your run. And it's even possible (and productive) to squeeze in activities such as active isolated stretching, leg swings, donkey kicks and the like during small breaks from work. Every little bit helps when you are pushing your body to the max.
Appreciate the Mundane
Admit it—when you think about marathon training, you think about long runs, tempos, repeats and other things that sound impressive and hard. The reality is that most days during your season are pretty mundane—a lot of miles at a generally easy pace. The "killer" workouts are (and should be) rare, and if they aren't, then you are risking burnout or injury. Don't fall into the trap of racing every workout, or seeing if you can stretch or speed up your recovery (anticipation) runs. Not every workout is going to go great, and it doesn't have to. The value comes from meeting the goals in that workout to the best of your body's ability on that given day.
The road to marathon success is paved with "nothing exciting" workouts, punctuated by the occasional blazes of glory. Don't get too caught up in the latter and risk taking the former for granted.
Simulate Race Conditions Several Times on Long Runs
Nothing gets you more ready for a race than rehearsing the elements of the event. From pre-run fueling to getting used to the fluids and gels they'll provide at the marathon to getting used to the profile of the course, each step helps you to eliminate the uncertainties that can derail your ambitions. There are several ways to achieve this:
Plan at least one run six to eight weeks ahead of the marathon in which you wear the clothes and shoes you intend to use, and try the fluids and gels provided by the race. Doing it early gives you a chance to try again in case there are issues like chafing, blisters, or an upset gastrointestinal system.
Try to simulate the hill profile of your event (if necessary) on several of your long runs. If you are running Boston, get used to doing a lot of downhill running early and uphills late on your long runs. Ideally, you'll want to practice this at marathon pace effort eventually so you get a sense of how hills will impact your pacing.
If your race involves long straightaways, be sure to incorporate those as well. Such straightaways can be mentally tough, so you'll be well-served to get used to the experience.
If your race is local, the best experience of all is to scout the course, preferably by doing one or more of your long runs on various segments. This will get you familiar with all of the nuances of the route, such as where subtle hills appear, or which side of the road will help you cut a tangent.